A phone number is typically required for security and verification purposes, but unlike Passport and Address verification, a phone number is not obligatory when withdrawing funds from your StocksTrader account. However, if you have enabled two-factor authentication via SMS, your mobile number is a must for processing the withdrawal request. If you are unable to receive an SMS with the confirmation code, you can try entering another phone number and attempt the verification again. If you encounter issues during the withdrawal process or with phone verification, please contact Live Support for further assistance.